<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <style>
    .stacked-linear {
      width: 300px;
      height: 300px;
      color: color-mix(in hsl, rgba(0, 255, 0, 1) 50%, rgba(255, 0, 0, 1) 50%);
      background:
          linear-gradient(90deg, rgba(0, 255, 0, 1), color-mix(in hsl, rgba(0, 255, 0, 1) 50%, rgba(255, 0, 0, 1) 50%), rgba(255, 0, 0, 1) 100%);
    }
  </style>
</head>
<body>
<div class="stacked-linear"></div>
</body>
</html>